<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>

</body>
<script type="text/javascript">
var month = "06",
    year = "09";
month = parseInt(month, 10);
year = parseInt(year);
console.log(month + "--" + year)
</script>
</html>